package com.baizhi.zjs.util;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class Sha256Util {
 
    /**
    * 利用java原生的类实现SHA256加密
    * @param str 加密后的报文
    * @return
    */
    public static String getSHA256(String str){
      MessageDigest messageDigest;
     String encodestr = "";
     try {
      messageDigest = MessageDigest.getInstance("SHA-256");
      messageDigest.update(str.getBytes("UTF-8"));
      encodestr = byte2Hex(messageDigest.digest());
     } catch (NoSuchAlgorithmException e) {
      e.printStackTrace();
     } catch (UnsupportedEncodingException e) {
      e.printStackTrace();
     }
     return encodestr;
    }
    /**
    * 将byte转为16进制
    * @param bytes
    * @return
    */
    private static String byte2Hex(byte[] bytes){
     StringBuffer stringBuffer = new StringBuffer();
     String temp = null;
     for (int i=0;i<bytes.length;i++){
      temp = Integer.toHexString(bytes[i] & 0xFF);
      if (temp.length()==1){
      //1得到一位的进行补0操作
      stringBuffer.append("0");
      }
      stringBuffer.append(temp);
     }
     return stringBuffer.toString();
    }
    //测试
    public static void main(String[] args) {
    	//===111111===bcb15f82 1479b4d5 772bd0ca 866c00ad 5f926e35 80720659 cc80d39c 9d09802a
		String sha256 = Sha256Util.getSHA256("111111");
    	System.out.println("===="+sha256);
	}
}